There have been suggested CNT/carbon fiber composite materials that have a structure in which a plurality of carbon nanotubes (hereinafter, referred to as CNTs) are entangled to form a CNT network thin film on the surface of the carbon fibers as composite materials (for example, Patent Literature 1). Patent Literature 1 discloses that immersion of a carbon fiber bundle in a dispersion in which CNTs are isolatedly dispersed followed by application of energy by, for example, vibrations, light irradiation, and heat, to the isolation dispersion enables a CNT network structure to be formed on the surface of the carbon fibers.